1. Field of the Invention
The present invention relates to mobile communication technology, and more particularly, to a method that efficiently scans a network intended to be selected by a mobile station, and to a mobile station using the method.
2. Description of the Related Art
In general, a mobile station (MS) selects a network by undergoing a public land mobile network (PLMN) selection procedure, for example. The PLMN selection procedure is disclosed in detail in a standard specification proposed by 3rd Generation Partnership Project (3GPP), i.e., “3GPP SPEC 23.122.”
The mobile station performs such a network selection procedure including, but not limited to, any of the cases where a mobile station initially powers up; a mobile station has lost its service coverage and is restoring said coverage; a PLMN is searched during a roaming operation; a user manually selects a specific PLMN.
To perform the network selection procedure, the mobile station must first scan to determine which networks are currently on the air. For example, to recognize which PLMNs are on the air, the mobile station must scan for a Broadcast Control Channel (BCCH) carrier frequency and read specific information included in a corresponding carrier.
Since, initially, a mobile station is only able to recognize a receive-level of a corresponding frequency, the mobile station usually reads frequency information in an order beginning with a highest receive-level of the frequency.
However, all of the frequencies are not BCCH carriers and do not allow information to be provided. Therefore, the mobile station must scan all of the frequencies on the air to determine available networks. Such a conventional method is disadvantageous because it wastes electrical power and incurs long wait times for users.